You can define vectors as (X, Y, Z)
for example (-1, 3, 5) assuming that the vector begins at point (0, 0, 0).
If the vectors starts at a point different from (0, 0, 0) you can define it as
(X1, Y1, Z1 : X2, Y2, Z2) for example (1, 2, 1 : 2, -1, 0)